A pair of suicide bombings that left 31 dead in Russia could be a chilling tune-up for the Olympic Games, where a Muslim terrorist leader has vowed to put Chechnya’s long-standing grievance with Moscow in the international spotlight, according to terrorism experts.

Although no one has claimed responsibility for the twin bombings, which occurred less than 24 hours apart in the city of Volgograd, formerly known as Stalingrad, terror experts strongly suspect they were inspired, if not ordered, by Chechen Muslim rebel leader Doku Umarov. Umarov, who calls himself the emir of the terror group the Caucasus Emirate, has called on Muslims to attack civilians and to prevent the Olympics from occurring.

The games, scheduled to begin in six weeks in Sochi, the Black Sea resort about 400 miles southwest of Volgograd, are "Satanic dancing on the bones of our ancestors," Umarov said in a video released online in July.

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The attacks, coupled with Umarov’s call for violence, will cast a dark shadow over the games, according to Bruce Hoffman, director of the Center for Security Studies and Director of the Security Studies Program at Georgetown University’s Edmund A. Walsh School of Foreign Service.

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“No Olympics in recent memory will commence as inauspiciously at the 2014 Sochi Games,” Hoffman told FoxNews.com. “Although fear of terrorist attack has been a staple of Olympics security for the past four decades, the back-to-back blasts yesterday and today, coupled with another attack in the same city in October, are likely intended to be the opening salvos in a sustained terrorist campaign.

“This would be unprecedented in Olympic history and likely reflects the perpetrators' intention to disrupt the games even before the opening ceremony," Hoffman added.

In the first attack, a bomber authorities believe may have been a woman detonated explosives in front of a metal detector just outside a train station entrance Sunday as a suspicious police sergeant approached to check the bomber’s ID. The officer was one of 17 killed by the blast. Hours later, early Monday, a suicide bomber on a bus killed at least 14 people and left nearly 30 wounded, Russian officials said. The bombs were similar, according to Vladimir Markin, the spokesman for Russia's main investigative agency.

"That confirms the investigators' version that the two terror attacks were linked," Markin said in a statement. "They could have been prepared in one place."

Following the most recent attack in Volgograd, Russian news outlet Lifenews.ru, posted what it claimed was an image of the severed head of the female attacker. The report said the woman’s two successive rebel husbands had been killed by Russian security forces in the Caucasus. Female suicide bombers, often widows or sisters of slain rebels, have mounted numerous attacks in Russia and are commonly referred to as "black widows."

In October, a so-called black widow blew herself up on a city bus in Volgograd, killing six people and injuring about 30.

Russian President Vladimir Putin had already deployed tens of thousands of soldiers, police and other security personnel for the games and implemented extensive identity checks and security measures. A security zone created around Sochi for the games extends 60 miles along the Black Sea coast and up to 25 miles inland. Russian troops will patrol the mountains that loom above the resort, drones will be deployed over Olympic facilities and cars will be banned from the zone starting a month before the games begin until a month after they end. On Monday, Putin announced that even more security forces would be deployed.

It's possible Umarov's operatives are already inside the security zone, said Jim Phillips, senior research fellow at the Heritage Foundation. Phillips said he "would be surprised" if there is not a terrorist attack during the Olympic games, but said he doubts it could be on a big scale.

"It is very likely that Umarov or others will try to disrupt the Olympics with a terrorist attack, and it is very possible they are already inside the zone," Phillips said. "But they will find it difficult to move weapons or explosives around inside the zone."

Experts say Umarov’s calls for indiscriminate violence have hurt the popularity of his group, and the possible use of female suicide bombers could further alienate Chechens. But even if he is unable to direct attacks, issuing a clarion call to suicide bombers could yield more independent attacks.

"An open question is how much authority he really has over these different groups," Jeffrey Mankoff, deputy director and fellow at the Center for Strategic and International Studies' Russia and Eurasia Program, told USA Today. "A lot of the attacks seem to be inspired by Umarov but may not be directly controlled by him."

The rift between Russia and Chechnya dates back hundreds of years, and Sochi and other cities in the region were captured by Russia in the 19th century. Umarov and others view the Olympics being held in Sochi a provocation, held in territory they consider stolen from Muslims, according to Mankoff.

Chechen Islamist separatists declared their independence from Russia in 1991, as the former Soviet Union broke apart. Russia reasserted its control over Chechnya in 1999, but several terror attacks in the North Caucasus have flared up since then, most notably the 2004 Beslan attack, in which Islamic militants took more than 1,100 people hostage in a school. The siege ended in the deaths of more than 380 people, including hundreds of children.

In 2010, two female suicide bombers mounted an attack in the Moscow subway that killed 40, and less than a year later, a male suicide bomber struck Moscow's Domodedovo Airport, killing 37 people and injuring more than 180. Umarov claimed credit for both attacks.

Chechnya is now run by Moscow-backed strongman Ramzan Kadyrov, a former separatist who has been credited with stabilizing the region.